


Nine-Nine!

by nu-exo (Nekohime)



Category: NU'EST, Wanna One (Band)
Genre: Alternate Universe - Brooklyn Nine-Nine (TV) Fusion, Competitive idiots, M/M
Language: English
Status: Completed
Published: 2018-10-16
Updated: 2018-10-16
Packaged: 2019-08-02 21:45:13
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 7,437
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/16313225
Author URL: https://archiveofourown.org/users/Nekohime/pseuds/nu-exo
Summary: Seongwu and Minhyun were the last people who should've been making a bet, considering they were by far the most competitive detectives in the precinct.





	Nine-Nine!

**Author's Note:**

> I had so much fun writing this! I love Brooklyn Nine-Nine to death and was so happy to see a prompt like this in the prompt sheet, so thank you to the prompter for submitting it. Thank you Mod Andie for the kind words during check-ins and for running this fest! To those who know the series, can you tell who's who? And to those who aren't familiar with it, give it a watch! It's a fun show with a great cast.
> 
> Hope you guys enjoy how this came out!
> 
> And, if you like it, leaving a comment or kudos is a great way to show that.

  
  
  
  
  


“NYPD!” Seongwu shouted, “Stop! In the name of the law!”

The criminal he was chasing — your typical b&e repeat offender — chanced a panicked glance over his shoulder before promptly tripping over a pile of garbage bags, taking a metal trash can down with him as he fell.

Seongwu, panting, muscles in his legs aching, pounced.  He grabbed the robber’s arms, quickly wrangling him into a pair of cuffs.

“You,” Seongwu panted just as Minhyun came around the corner up-ahead, “are under arrest.”

“How did you-” Minhyun frowned, barely even breathing hard despite the fact that he’d definitely been running too.  “I was ahead of you.”

“What can I say,” Seongwu smiled, giving him a cheeky wink.  “I’m a master of the chase. My speed knows no bounds. I’m like a cheetah-”

“You cut across the construction site two blocks over, didn’t you?”

Seongwu scoffed, tugging the robber along to start heading back to their car.  “I’m insulted, you think I can’t catch a perp without-”

“You have concrete dust in your hair, on your shoes, on the hem of your pan-”

“Fine, fine, I get it, you’re right. Doesn’t change the fact that this is my collar, therefore one more point for Top Detective Ong.”  The robber they were carting off snorted. Seongwu pouted. “You don’t get to laugh. What kind of thief doesn’t wear gloves when they steal shit?”

“Not a very good one,” Minhyun agreed, unlocking their car’s back door so Seongwu could push the robber in, ignoring the man’s indignant  _ Hey! _

Criminal secure, Seongwu turned to face Minhyun, shit-eating grin plastered on his face.  He took a moment to appreciate how good Minhyun looked in his button up and slacks, a little color in his cheeks from running in the brisk winter weather.  

Seongwu held out his hand.  Minhyun looked from it, to Seongwu’s face, then back again.

His lips twisted into what had to be an unconscious pout, because he was much too mature to resort to it consciously.  That was more of Seongwu’s thing.

“Please let me drive.”

Seongwu’s grin grew.  “Winner’s rights. I collared the bad guy, therefore  _ I _ get to drive.”

Minhyun made a small noise of despair, reluctantly handing over the car keys.  Seongwu happily snatched them away and slid into the driver’s seat, adjusting all the mirrors while Minhyun sulked his way into the passenger’s side.

“Ready?” Seongwu chirped, looking over at Minhyun.

Minhyun groaned, sinking a bit in his seat.

“Great! Let’s ride!”

  
  
  
  


Seongwu strutted in to the nine-nine’s briefing room with his chest puffed out and a saunter in his walk.  Minhyun trailed in behind him, petty glare burning a hole in the back of his head.

“Guess who caught the 9th Street Burglar,” Seongwu smirked, dropping into the seat next to Daniel, leaning back in his chair and lacing his fingers behind his head.

“Oh no,” Minki laughed, eyes glittering as he watched Minhyun drag his feet to the whiteboard at the front of the room.  “You got to drive back, then?”

“He blasted teeny-bopper songs the entire way here,” Minhyun grumbled under his breath, uncapping the dry-erase marker with more force than necessary.

“No one says ‘teeny-bopper’ anymore,” Nayoung commented dryly from the corner of the room she’d situated herself in, feet up on the table.

“Now, now, we shouldn’t gang up on old man Hwang,” Seongwu said, like the magnanimous soul he was.  Minhyun looked over at him, hopeful smile on his lips that said he’d take what he could get, when Seongwu continued, “He’s in the middle of doing something  _ very _ important. Besides, it’s not his fault he doesn’t know any music from this century.”

Minhyun’s expression fell flat and unamused, rolling his eyes as he erased the eighty-two in the box under Seongwu’s name and wrote a tiny, barely legible eighty-three in its place.  It didn’t stop it from being larger than Minhyun’s eighty-one in the box next to it.

“Happy?” Minhyun said, slapping the marker back down and turning to the teasing applause of the rest of the room.

“Very,” Jonghyun deadpanned, walking in.

Minhyun immediately went red, freezing like a deer in headlights.  “Captain. Good morning. Didn’t see you there, sir.”

Seongwu snickered, covering it up with a cough when Captain Kim turned his disapproving stare on him.  “Morning, Cap. Any new cases on the board?”

“I thought I told you two to keep your bet out of the briefing room,” Jonghyun commented mildly, taking his place at the front of the room, passing by an embarrassed Minhyun who eked out a,  _ “Sorry, sir, won’t happen again, sir” _ as he skittered into the nearest empty seat.

Unfortunately for him, that seat was right in front of Seongwu’s, making it all too easy to lean forward and whisper, “Teacher’s pet.”

“Class clown,” Minhyun shot back, not missing a beat.

“Detectives,” Jonghyun said.

“Sorry, sir,” they both mumbled, with varying degrees of sincerity.

Jonghyun sighed, shuffling the papers in his hands as he began their morning rundown.  “To start with, good work Detectives Hwang and Ong on your speedy investigation and arrest of the 9th Street Burglar. I’m glad to see there’s at least  _ one _ good thing coming from this inane bet you two have started.”

“Thank you, sir!” Seongwu called out.

Jonghyun sighed again.  “Detective Kang, Detective Im,” Seongwu discreetly nudged Daniel — whose head was drooping towards the table — awake with a well placed elbow, “What’s the status of the Baker shooting?”

“We arrested the killer yesterday, sir,” Daniel said just a touch too loud, trying to blink himself to full awakeness.

“ADA Wilder is sending someone today to pick up the case files and evidence,” Nayoung continued.

“Good,” Captain Kim nodded, “Next, Sergeant Kang?”

“An arrest was made in the Rivera case. Everything’s been handed over to the DA and all that’s left is to write up the statement summaries,” Dongho reported, sitting up in his seat with perfect posture, button-up stretching over his biceps and chest in a way that  _ did not _ make Seongwu jealous.  If not even  _ Minhyun’s _ nagging could get him to work out, nothing could.  “Oh, and I broke up a fight between Park One and Park Two this morning.”

The whole briefing room watched the Captain’s face with bated breath, money swiftly exchanging hands as a muscle by his right eye just barely twitched in exasperation before he could reign himself in.

“Detectives Park and Park.”

“Yes, sir?” Woojin and Jihoon both responded, wary.

“Why?”

“Jihoon bet me twenty bucks I couldn’t eat an entire sub in under five minutes.”

“No normal person should be able to,” Jihoon muttered.

Woojin glared at him.  “And, when I won, he didn’t pay up.”

Jonghyun blinked.  Once, twice, took a deep breath.  “So you...punched him?”

“Of course not, Captain,” Woojin scoffed.  “I put him in a headlock, and then  _ he _ hit  _ me _ .”

Seongwu had to bite back a smile.  Detectives Woojin Park and Jihoon Park were the youngest in their squad.  When they were on their A-game, they could give even Seongwu a run for his money in terms of case closing efficiency.  Unfortunately, they picked and poked at each other over the stupidest things ninety percent of the time. The other ten percent, they were causing trouble for everyone else.

Next to Seongwu, Daniel was shaking with his own silent laughter, looking down at the table so as not to draw Captain Kim’s attention.  Captain Kim, of course, saw everything — something Seongwu had learned the hard way.

“I expect you two to comport yourselves better in the future,” Jonghyun said, making the Park demons wilt, “and, Detective Kang, you can take over the Sergeant’s role in supervising them.”

Daniel made a noise of distress and Seongwu clapped him on the back, everyone else snickering at the other detective’s misfortune.  Woojin and Jihoon groaned. Daniel worked cases, but, after an incident with a mannequin and his firearm, he didn’t run lead. And, Jonghyun never sent out more than two detectives on a case, let alone four.  It was a neat way to unofficially bench them.

“Now,” Jonghyun said, patting the stack of folders he’d brought up to the podium with him, “Onto our next order of business.”  He picked up one of the folders and held it out. “There was a murder on 5th. Hwang, I want you and Im to head out there ASAP.”

“Yes, Captain.”  Minhyun got up to take the folder, smirking at Seongwu as he and Nayoung headed out.

Annoyance at Minhyun and himself had Seongwu’s eye twitching.  Minhyun, because excuse him, how dare he smirk at Seongwu? Seongwu was the one in the lead right now with only a month left in their bet.  And, himself, because at the end of the day Minhyun smirking was so very, very  _ hot _ and Seongwu was so very, very  _ weak _ .

Sitting forward, Seongwu gave Jonghyun his best and brightest smile, eager to get his case and hit the street.  “What about me, Cap?”

“Jewelry store robbery gone bad.”

Seongwu bounced out of his seat, snatching the folder from Jonghyun’s hand.  “This wouldn’t happen to be connected to the Diamond Drop Bandit, would it?”

Captain Kim sighed.  “Sergeant Kang will work with you. Behave yourself.”

“I am insulted you think that-”

“I’ll keep an eye on him, Captain,” Dongho cut in.

Seongwu made a face at him, which Dongho just snorted at, before all but floating out of the briefing room, hearing the Captain tell Daniel to wait for the ADA on the Baker case and the Park demons grumbling about desk duty as he went.

Catching the Diamond Drop Bandit would be such a  _ wonderful _ way to win the bet.

  
  
  
  
  


The Bet to Prove Seongwu Ong is the Greatest Detective Ever started with what should’ve been a harmless comment.  Because the comment had come from Minhyun, though — who Seongwu had been wanting to pounce on since he first walked in to the precinct — it had been anything but.

“You know,” he’d said, amusement making his eyes fucking  _ twinkle _ , “if you tried half as hard on your cases as you did on flirting, you could be the top detective in the precinct.”

Seongwu had scoffed around a mouthful of sandwich.  “Excuse you, I  _ am _ the top detective in the precinct.”

Minhyun had raised an eyebrow and smiled wider in response.  The fact that Seongwu hadn’t denied or commented on the flirting bit of his observation not escaping him.  

He’d leaned forward, smile turning a touch smug at the way Seongwu had frozen and said, “Not anymore you aren’t.”

Predictably, considering their relationship was fifty percent cheeky banter and fifty percent competition — they’d both grown up with overachieving older sisters — things escalated.  Hence, The Bet.

If by the end of the year Seongwu had more arrests, then Minhyun had to agree to a date and say that Seongwu was The Best Detective to Ever Detective.  If Minhyun won, though, then not only did Seongwu have to publicly declare that Minhyun was the better detective, but he’d have to give Minhyun his precious 1971 Mustang for a whole week.

The terms were written on an old take-out menu in dry-erase marker and then shaken on with the whole squad as their witnesses.

Eleven months later and victory was so close Seongwu could  _ taste _ it.  Bar a Christmas Miracle, there was no way Minhyun would catch up.

  
  
  
  
  


“It’s a Christmas Miracle!”

“No!” Seongwu cried, watching in horror as Minhyun and Nayoung marched in not one, not two, but  _ three _ men in handcuffs.  “ _ How?” _

“We caught these three goons trying to destroy evidence in a warehouse one of them owned,” Nayoung explained, handing off her guy to a uni to take to processing.  “They kept arguing about whose fault it was they got caught all the way here. It was awful.”

“On the bright side,” Minhyun chirped, coming to stand by Seongwu’s desk, smug ass smile curving his eyes into pretty crescents, “I’m officially in the lead.”

Seongwu felt his eyebrow twitch.  “For now.”

“You sure?”  God, Minhyun was fucking  _ glowing _ .  “Because, judging by the state of your desk, things don’t seem to be looking so hot for you,  _ Mr. Top Detective _ .”

“Hah! Shows what you know. My desk is always a mess.”

Minhyun made a face at that — a cross between disgust, distress, and resignation — but it was Dongho, sitting over at his own desk, who responded.

“Trust me,” he snorted, looking up from the evidence report he’d been poring over, “Minhyun is aware. It’s on his ‘Cons’ list.”

Seongwu scrunched his nose.  “His cons list of what?”

“Of nothing!” Minhyun quickly cut in, shooting Dongho an irritated glare, his ears burning.  “He doesn’t know what he’s talking about.”

“Sure I don’t,” Dongho smiled back, thoroughly unphased.  When you worked in the same precinct as Nayoung, few things scared you.  “Anyway, Seongwu, come over here for a sec. I think I found something.”

“Oh thank fuck,” Seongwu sprung out of his chair, almost tripping over the legs of his desk as he went.

“Hey,” Minhyun pouted, “I’m not done gloating yet.”

“You can flirt with him later,” Dongho said, ignoring Minhyun’s sputtered out  _ “I’m not flirting!” _ in favor of pointing out what he’d found to Seongwu.  “Look, they thought these prints were just from a customer, but…”

“But they’re in the back room of the first store that was hit!” Seongwu grinned.  “Awesome! Let’s go!”

Seongwu skidded back to his desk, grabbing his puffer jacket off the back of his chair and flashing Minhyun a giddy smirk as he shrugged it on.  “Enjoy being in the lead while it lasts.”

Minhyun crossed his arms over his chest, eyes narrowed, watching Seongwu all but run to the elevators like a kid on a sugar high, Dongho trailing behind him.  “You’re not going to pass me with one bust.”

“So you say,” Seongwu sing-songed, bouncing on the balls of his feet.  “Hey, when I win this bet, how should I celebrate? Would throwing a party be too much?”

“You look like a stupid marshmallow in that jacket,” Minhyun snapped, turning to go back to his desk.

“A soon-to-be loser’s pettiness has no effect on me!” Seongwu crowed, hopping into the elevator.  Then, through the closing doors, “And I look damn cute in this jacket!”

  
  
  
  
  


“I thought it was just a bunch of jewelry store robberies,” Minhyun blanched when Seongwu, Dongho, and a small team of unis came into the precinct with a line of six men in handcuffs two days later.

“It was,” Seongwu smiled.  He’d spent the entire night on stake-out and still hadn’t slept, but he’d never felt better.  “Meet Jeff, Richard, John, Johnny, Emmet, and Mikey. The Beeman brothers, also known as, wait for it,” he waved his arm in a grand sweeping gesture, “the Diamond Drop Bandits.  _ Plural _ .”

“You’ve got to be kidding me.”

Seongwu happily helped lead the men into their holding cells.  “Nope. Isn’t this great, though? I’m winning again!”

“No,” Minhyun groaned, watching Seongwu skip over to their scoreboard.

Captain Kim had made them move it from the briefing room on the basis that it was, “Causing too much of a disturbance every morning, Ong”, so now it was smack dab in the middle of the bullpen.  Much less obtrusive, obviously.

“Hey Hwang, how does it feel to be two steps behind yet again?”

“He left.”

“ ‘hat?” Seongwu turned around, marker cap in his mouth.

“Yeah, halfway through you bragging he walked out onto the balcony saying something stupid about it being a beautiful day out even though it’s like, below thirty,” Minki drawled, adding another paper crane to the already impressive pile on his desk.  “He’s probably smoking the rest of his spare emergency cigarettes that he supposedly doesn’t have.”

Right when he finished saying that, Woojin walked in to the bullpen, shaking off the cold from the outside.

“Why is Minhyun hiding in the corner of the balcony pretending not to be smoking three cigarettes at once? It’s freezing out there.”

“Knew it,” Minki smirked, leaning his elbows on his desk.  “Did you get a picture for the Nine-Nine Wall of Shame?”

“It was freezing,” Woojin repeated, as if that explained everything.

“Is that a no?”

“It’s a no.”

“Ugh, you’re useless,” Minki sighed, flopping back in his seat.

Seongwu snorted at the face Woojin made in response.  Park 2 clashed the most with the Captain’s assistant since, everytime they broke something in the precinct, it was Minki who came chasing after them, promising hell to pay for disturbing the vibes of his “domain”.  It also meant they’d developed a certain amount of immunity towards his comments and general existence. 

“Why were you even out there in the first place?” Seongwu asked, walking over to drop into the chair by Minki’s desk.

Woojin froze before firing back, “Why was Minhyun out there? Didn’t he quit smoking last month?”

“Tried, but caved everytime he got stressed, which is always, so now he says he doesn’t and we all pretend to not know that he does.”

“Then why is he smoking now?” Woojin frowned.  “I thought he was-” he registered Seongwu’s shit-eating grin, “Ohh. Got it.”

“So,” Seongwu leaned forward, not the least bit distracted by that weak-ass attempt to change the topic, “Why were you out there again?”

“The sky looked very pretty?”

Seongwu raised an eyebrow, eyeing the crumbs dusting Woojin’s shirt and the mustard smeared on the corner of his mouth.  “Oh? So, it wouldn’t have anything to do with the sandwich from George’s Deli that Jihoon brought for lunch today and  _ specifically _ told you  _ not _ to eat or, and I quote, he’d  _ make your body disappear _ .”

“No.”  Woojin cleared his throat, casually brushing a hand down the front of his shirt.  “Of course not.”

“Of course not,” Seongwu snorted, “Silly me.”

“Don’t you have anywhere better to be?” Woojin grumped, crossing his arms over his chest defensively.

“As a matter of fact, I do,” Seongwu said, standing.  He turned to Minki, catching him swiftly hiding his phone under his desk.  Seongwu would bet the thirty-five dollars, four cents, and Duane Reade savings card in his wallet that Minki had been taking a proof shot of Woojin to be used as blackmail at a later date.  Ignoring that — Seongwu wasn’t going to interfere and risk having his own blackmail worthy images aired — he asked, “Is the Captain in?”

Minki went back to folding what looked like official documents into paper cranes.  “Nope,” he popped the ‘p’ like a bubble, “You just missed him. Why?”

“I was hoping for another case. If he’s not here, though, then I guess I’ll wander around and see if I stumble on a crime.”

“Poor Minhyun,” Minki hummed, slapping a paper crane out of Woojin’s hand, hissing a warning,  _ “Don’t touch.” _

“Oh please,” Seongwu snorted, checking his jacket pockets to make sure he had everything he needed.  “The second he relaxes enough to think properly he’s gonna go back to figuring out how to catch up. He’s annoying like that.”

“Uh huh,” Woojin drawled, smirking, “Annoying.  _ Sure _ .”

Seongwu leveled him with his best unimpressed stare.  “I don’t suppose Jihoon knows you have a folder called ‘Lesser Park’s Best Pics’ saved on your computer, does he?”

“Oh, would you look at the time,” Woojin laughed nervously, looking down at his watchless wrist.  “I’ll just be,” he flailed his arm in the vague direction of his desk, “around. Bye.”

“He’s got it bad,” Seongwu snorted, watching the younger detective beat a truly impressive hasty retreat.

“Like you don’t?” Minki scoffed, raising his brows in amusement when Seongwu quickly devolved into a sputtering mess trying to defend himself.  “Anywho,” he continued, “Minhyun’s Not-Smoke Breaks Smoke Breaks usually take about ten minutes, so you might want to leave soon.”

Seongwu valiantly collected himself, clearing his throat with a cough, hyper aware of the heat creeping up the back of his neck.  “If the Captain comes back before I do, tell him I went to get food or something. If Minhyun asks, feel free to brag that I’m a winning winner who wins.”

“Mm, I’m gonna have to say no to both those things.”

Not listening, Seongwu jogged over to the elevators, hopping in just as the doors were closing.  “Honey, don’t wait up!”

  
  
  
  


Of course, the universe would apparently fall apart if Minhyun didn’t immediately catch up the second Seongwu was in the lead.  And with the same plan Seongwu had been planning to use too.

“Borrowed Woojin today,” Minhyun explained sunnily, depositing a man in their holding cell that looked like he’d seen better days.  “Turns out he really does attract trouble everywhere he goes.”

Okay.  So he used a better plan.

“Please tell me Woojin wasn’t the one that beat that guy up,” Daniel paled, eyeing the perp’s bruises and bloody nose.  “Captain Kim still hasn’t given the official ‘ok’ for him and Jihoon to go back to out on cases. If Woojin did that-”

“Have a little faith,” Woojin pouted, walking into the bullpen with another two men.  Also roughed up. “They were like this when we arrested them.”

“We broke up a gang organized fight club!” Minhyun announced, smiling.

His cheeks were flushed and his hair, which had been styled up earlier in the day, was limp and sticking to his forehead.  His usually immaculate clothes were rumpled and sweat damp, probably from running after perps. Actually, if Seongwu looked closer, Minhyun’s very nice slacks were dusted with dirt; something that would’ve normally driven neat-freak Hwang up a wall.  Despite all that, though, he was absolutely radiant. 

Excitement, even if it was over competing against Seongwu (maybe especially if it was over competing against Seongwu), suited him.  It made him look so upsettingly attractive. If he didn’t have so much riding on this bet, he’d probably let Minhyun win just to see his stupidly cute celebration dance.

_ I’m so very fucked _ , Seongwu huffed, biting his lip to keep the fond smile off his face.  You never knew where or when Minki and his stupid camera would strike.

“How’d you get Vice to let you help out with a sting?” Nayoung asked, coming over to stand by Seongwu’s desk.  “Last time I had a case that overlapped with one of theirs they acted like a dog protecting its favorite chew toy. It was annoying”

“I asked nicely,” Minhyun shrugged.

The disbelief rolling off everyone in the room was palpable.  Even Daniel — sweet, smiley Daniel — was staring at Minhyun like the man had grown another head.

“Seriously,” Nayoung said, raising an eyebrow.  “How?”

Minhyun sighed, rolling his eyes.  “Fine. I told Sungwoon he could use Babylon.”

“You what?” Minki screeched, skidding into the bullpen at the same time that Nayoung ground out a menacing, “You better be lying, Hwang.”

“It’s only for a week,” Minhyun quickly defended, taking an instinctual step back.  “His floor’s men’s bathroom had a pipe burst. All the guys are using the family bathroom now and, well, he already knew about Babylon anyway.”

Minki spun around to glare at them all.  “Which one of you rats told?”

“Dongho let it slip to him last month,” Minhyun immediately spilled.

Loyalty had no place in the face of an angry Minki Choi, let alone in combination with Nayoung.  Minki held grudges like no one Seongwu had ever met — he would know, they’d grown up together — and Nayoung was just flat out scary.

Minki clicked his tongue.  “Damn. Can’t do anything against him and all his muscles.”

“Sure you could,” Seongwu laughed.  “You have an entire folder of embarrassing photos on Daniel, and he has muscles. Even Minhyun has muscles. That has literally never stopped you.”

Minki just blinked at him like he was stupid before turning back to Minhyun with a sigh, “I guess I can’t do anything if it was Dongho, but you better make it clear to Sungwoon what’ll happen if he ruins Babylon.”

His threat delivered, Minki floated back out of the room to do...whatever it was he’d been doing before.

“You might want to emphasize to Sungwoon, that if he cares about his life — and yours — he’ll keep Babylon in perfect condition,” Nayoung said.  “And I mean  _ perfect _ .”

And then she was gone too.

“I really hope you didn’t only get two collars out of this,” Seongwu snickered.  “Because I’m pretty sure Nayoung could make your body disappear, and Minki would help her.”

“I got ten,” Minhyun said, and fuck, ten gave him a solid lead considering there was only a week and a half left.  “I’m not sure it was worth it though,” he frowned, chewing on his bottom lip in a way that absolutely did  _ not _ make Seongwu think about all the things he’d like to do to said bottom lip, “Think I can back out of the deal? Trade something else?”

“Sungwoon is small but mighty,” Daniel snorted.  “He’ll make your life hell if you back out now.”

Minhyun groaned, coming over to drop into his chair across from Seongwu.  He draped an arm over his eyes, sinking further into his seat, evidently happy to let Woojin and the uniforms handle bringing in the rest of the men.  

“At least I’m winning.”

“Mhm,” Seongwu hummed, smile slowly spreading.  “At least you’re winning.”

Minhyun peeked out from under his arm, gaze unguarded, open.  He looked tired. Soft. Seongwu’s fingers twitched. He wanted to tuck Minhyun in with a blanket, get him something warm to drink, and card his fingers through his hair until he fell asleep.  All domestic things Seongwu never did. With anyone. Fuck.

“Please don’t say ‘for now’,” Minhyun sighed, the request sounding more like a whine.

Seongwu grinned.  “Why would I? You already did it for me.”

  
  
  
  


Monday of the last week of their bet found both Minhyun and Seongwu standing in Jonghyun’s office, trying to speak over each other like a pair of bickering kids.

Seongwu had managed to convince Daniel into letting him borrow Jihoon behind the Captain’s back.  He figured if Woojin drew trouble like a magnet, logic follows that it’d work the same for Jihoon, so why not put that theory to the test.  It had even worked. Sort of. 

They’d been grabbing food when a pack of five idiots drunk in the middle of the day approached them.  Apparently, Seongwu and Jihoon had just been too tempting to resist, sitting there, stuffing their faces like they’d never seen food before, displaying table manners that would’ve given Minhyun an ulcer if he’d been there to witness them.  Seongwu had ignored their attempts at conversation, but Jihoon had told them to buzz off; enough response for the group’s leering leader to saunter over and drape an arm around Jihoon’s shoulders.

That had gone over about as well as if the guy had punched Jihoon in the face.  When Jihoon ground out that he was a cop, the lead idiot laughed and slid his hand up Jihoon’s thigh, slurring something about being into roleplaying also.  Seongwu really couldn’t emphasize enough that punching the young detective would’ve had better results.

A lot of shoving, shouting, and manhandling later, Seongwu had five new arrests to his name and Jihoon was nursing a bad temper and a split lip.

Seongwu had been happy to catch up to Minhyun’s score.  Jonghyun, after Jihoon had come back and promptly picked a fight with a confused Woojin, was decidedly nonplussed.  One could even say he was angry. Or disappointed? Probably a lot of both.

So.  Here they were.

“Enough,” Jonghyun finally said, raising his voice to shut Minhyun and Seongwu up.  “I thought I told you two not to let this bet interfere with police business.”

“We haven’t.”

“It’s not!”

Captain Kim stared at them.  And stared. And stared. Minhyun fidgeted.  Seongwu tried to hold the Captain’s gaze but the man.  Was not.  _ Blinking _ .

“Damn,” Seongwu hissed, rubbing at his watering eyes.  “How do you  _ do _ that, Cap?”

Jonghyun kept staring.

Seongwu made a gurgling noise.  “Fine! Fine. Minhyun  _ might _ be letting the bet interfere with our work a  _ little _ .”

“Hey!” Minhyun snapped, punching Seongwu in the arm, hard.

“Ow, okay,  _ I’m _ letting it interfere with our work. But, to be fair, I could’ve never imagined we’d come across a group of handsy drunks in the middle of the day, sir. Or that they’d pick a fight with Detective Park.”

“Jihoon wasn’t even supposed to be out on the streets. His unofficial desk duty hasn’t been lifted yet.”

“Hah,” Minhyun laughed, covering it up with a cough.

“Don’t think I don’t know you took Woojin out with you on that Vice sting, Hwang.”

Minhyun immediately deflated and Seongwu snickered out a not-so-quiet, “Busted.”

Captain Kim fixed him with a pointed look until Seongwu cleared his throat and lowered his head in a more deferential stance.  Sighing, Captain Kim folded his hands together on his desk, looking between his detectives.

“Since this bet is becoming such an issue, and you two are now tied according to your,” he leaned to the side, looking at their repurposed briefing room whiteboard with a slight disapproving curl to his lip, “scoreboard, allow me to assign you your next case.”

“Awesome,” Seongwu clapped his hands.  “Do you think I could get mine first?”

Minhyun swiftly elbowed him, aiming for the softness of Seongwu’s side that he knew was a weak point.

“No,” Captain Kim said, pursing his lips.  “You two will be working this case together. And yes, that’s an order, not a suggestion, Ong.”

Seongwu whined while Minhyun’s expression went pinched, obviously trying to bite back his own complaints.  Unlike Seongwu, Minhyun had too much pride to be a brat in front of the Captain.

“It’s a missing person’s case that’s about to be classified as cold, but since you two are such skilled detectives, I’m sure you’ll be able to solve it in the remaining,” he glanced down at his desk calendar, “six days you have. I’ll even approve overtime for the weekend.”

“I don’t suppose we could have a different ca-”

“No, you may not.”

Minhyun deflated.

“Cool,” Seongwu said, mind whirring as mild panic set in, rocking back and forth on his heels.  A cold case meant no leads, and they didn’t have much time. “Cool cool cool, very cool.”

“I expect you both to behave like adults when you go out there. I am not running a daycare.”

Daniel opened the door then, sticking his head in.  His hair was standing up in tufts and he was chewing his lip in worry.

“Um, Captain? Just thought you should know, Jaehwan is here from the eight-seven, and Jihoon and Woojin are eating off the floor.”

Seongwu snorted, pressing his lips into a line to keep from smiling, looking back to see the Captain’s reaction.

Captain Kim just blinked, taking a slow, deep breath in.

“Well, we better get right on this case, Cap,” Seongwu said while Jonghyun was still frozen, tone bright, grabbing Minhyun by his wrist and dragging the other man out with him.  “Don’t you worry about us. We’re all professionalism. We breathe professionalism!” he squeezed them past Daniel’s stupidly broad frame, ruffling the younger man’s hair, “We won’t let you down!”

  
  
  
  


They were going to let him down.

“Ughh,” Seongwu groaned, tipping back in his chair, draping his arms over the armrests like the limp noodles they were.  “This is impossible.”

Minhyun, slumped in his chair in a similar position, letting out a low whine.  “I wanted to impress the Captain.”

Seongwu gasped, raising his head enough to give the other man a look of mock offense.  “For shame, detective. This is a crime we’re investigating.”

“Oh please,” Minhyun said, scrunching his nose at Seongwu.  “You only want to solve this so you’ll win.”

“No,” Seongwu defended, lazily spinning his chair with his legs.  “I want to solve it because it’s a case. Plain and simple.”

“Proving to the Captain that you can solve a cold case and the prospect of winning has  _ nothing _ to do with it?”

Seongwu shrugged, stopping his momentum and blinking until his surroundings came back to a standstill.  “Eh, maybe a little.”

Minhyun snorted, small smile playing on his lips.  It was late on Wednesday night. Their floor was empty besides them and the handful of unis who were on-call.  The usual bustle and activity of the nine-nine was replaced by a quieter, calmer atmosphere. It made Seongwu’s eyelids feel heavy, his mind foggy with the need for sleep.  Minhyun must’ve felt the same, because he’d discarded his tie and undone the top buttons of his shirt in favor of comfort. He was blinking slowly, warm gaze settled on Seongwu like a blanket.

Seongwu wondered what he saw.  He hoped he liked it, even if it was just on a visually pleasing level.  At the end of the day, that’s all this bet was about anyway. Getting Minhyun’s attention.  Holding on to it.

_ How can I love you so much, _ Seongwu wondered,  _ when I don’t even remember starting to like you in the first place. _

“If you’re tired, you should go home, Seongwu.”

Seongwu blinked, eyes refocusing.  “Hm?”

Minhyun huffed out a soft laugh.  The smile he was giving Seongwu looked so...fond.  It took a lot of effort not to read too much into it.

“You’re falling asleep staring at me. You should go home and get some sleep.”

“Nah,” Seongwu yawned, stretching, making a small satisfied noise when his back popped.  “I couldn’t let you stay here working by yourself. I do have some sense of responsibility, believe it or not.”

“I believe it,” Minhyun smiled, “but what makes you think I’m gonna stay here?”

“You brought your blue travel pillow and a blanket, both of which are currently tucked in your desk. I also saw a spare set of clothes stuffed in your bag.”

Minhyun opened his mouth, closed it, opened it again.  “That proves nothing.”

Seongwu snorted.  “Sure. I’m gonna make a run to the 24/7 coffee place down the block. You want anything?”

“It’s fine, I’ll come with you.”  Minhyun stood up, shrugging on his coat and doing up his buttons.  “I could use the walk and fresh air.”

Seongwu’s lips tilted up into a lopsided smile, teasing.  “You know, if you wanted to spend time with me there are easier ways than pulling an all-nighter.”

“Shut up,” Minhyun mumbled, his ears turning red in the way Seongwu had come to find painfully endearing and absolutely adorable.  “Come on, get your jacket and let’s go.”

Seongwu blinked, then scrambled to get up, definitely overly eager.  Minhyun laughed at him, loud and open. Seongwu’s heart hiccuped in his chest.   _ He didn’t deny it. _

It was almost two in the morning and cold as fuck outside, but Seongwu found that with Minhyun walking next to him, laughing at his stupid jokes, he really couldn’t bring himself to care.

  
  
  
  


Seongwu spent more time with Minhyun in the days leading up to the bet’s end than he had in the past year.  They got their meals together, poring over case files and evidence folders, heads bent close. When it got too late and they needed to sleep on an actual bed, they’d drive to Seongwu’s place to crash.  Seongwu discovered two more things he liked about Minhyun through that:

 

  1. Minhyun’s bed hair.  It make him look fluffy and touchable, not like his usual put together prince amongst commoners image.
  2. Minhyun in Seongwu’s clothes.  They were just that side of too tight on him and made him look absolutely _delicious_.



Unfortunately, despite all these sudden progressions in their friendship (possibly, hopefully, relationship?), they weren’t getting very far on their case.  Sunday morning, the last day of their bet, they were stuck.

Looking at the facts they had and the things they’d discovered in their investigation, Seongwu knew they were close.  They were just missing  _ something _ .  It was bugging Seongwu like an itch he couldn’t scratch.

“What happens if we end in a tie?” Minhyun asked, voice muffled from how his face was pressed against his desk.

“It’s not going to end in a tie,” Seongwu said absently, frowning down at one of the evidence reports.  

They’d found a body — not their missing person’s — at one of the spots their missing used to frequent.  An acquaintance of the guy they were actually looking for. A pair of work boots had been missing from the old apartment, and it seemed like the guy had been bringing groceries despite not living there.  Neither their missing or their victim lived there, actually. It supposedly belonged to yet  _ another _ dude who they  _ also _ couldn’t find. 

Seongwu ran a frustrated hand through his hair, gnawing on the end of his pen.   _ It has to all be connected. Somehow. _

“God,” Minhyun groaned, lifting his head.  He rubbed at his eyes, flipping through the statement they’d gotten from their missing’s wife.  “Is this guy even actually missing? I swear, if it weren’t for the abandoned car and blood we found on the car seat, it’d look like he just decided to take some cash and disappear.”

Seongwu paused mid-reach for the dead guy’s phone records.  “That’s it.”

“What’s it?” Minhyun asked, dropping his chin in his hand, not really paying attention.

“Our missing, isn’t missing.”

“How? He hasn’t been seen in months. The only reason the higher ups don’t want this running cold is because of his wife’s connections.”

“And the chunk of money taken out of their joint account last month,” Seongwu pointed out, smiling.  “His wife said she didn’t authorize that.”

“Yeah, and the previous detectives looked into that. They chalked it up to identity fraud.”

“What if it wasn’t?”

Minhyun frowned, thinking.  “What if it was her missing husband…”

“Who’s not so missing,” Seongwu finished.  “Come on,” he grabbed his keys, “I’m driving.”

“Driving where?” but Minhyun was already standing, grabbing his coat, scarf, and gloves.

Seongwu bounced over to him, wearing the puffer jacket he knew Minhyun secretly loved — courtesy of the little tells Minhyun wasn’t even aware he had — and waggled his eyebrows.

“To solve our case!”

  
  
  
  


“NYPD!” Seongwu shouted, vaulting over a shrub.  “Stop running Mr. Jennings!”

He chased their “missing person” down the suburban street, his lungs screaming from the workout, sweating under his layers even in the cool evening air.

“Why do they always run,” Seongwu grumbled to himself between breaths.  Then, louder to the startled elderly couple walking their dog ahead of him, “Excuse me! NYPD, coming through!”

The couple hurried further out of his way, their little dog yipping at him as he passed.

Seongwu was starting to think Earle Jennings — who was very much alive and well and  _ not missing _ , and  _ damn _ , Seongwu was good — was going to get away, the man’s head start not letting Seongwu catch up.  So, obviously, that’s when Minhyun came barreling down a side path to tackle Jennings onto one of the many manicured lawns around them ( _ “Wouldn’t be the suburbs without ruler-measured lawns as far as the eye can see” _ ).

Despite the fact that it’d looked like a solid and painful impact, Jennings immediately tried to struggle up, cursing Minhyun and throwing elbows.

“A little help,” Minhyun grunted, narrowly dodging a hit to the face.

Seongwu quickly dropped down next to him, helping wrangle the perp’s arms into a set of cuffs.  

“Good job,” Seongwu panted, half-grudging half-impressed.  Watching Minhyun in action was always impressive. “I guess that means you win, huh?”

“Really?” Minhyun asked.  Compared to Seongwu who was still gulping air like a fish, he was barely even breathing hard.  So not fair. “Pretty sure this one’s yours.”

“Huh?”

Minhyun laughed at Seongwu’s confused expression, eyes curving up into crescents.  “You figured it out. This idiot was never missing. Just skipping out on his wife with her money and a younger woman.”

“Yeah, but you caught him. Literally.”

“Just take it, Seongwu. It wouldn’t feel like a win if I got it just by being in better shape than you.”

Seongwu scoffed at that, mildly offended but unable to deny that yes, Minhyun was in ten times better shape than he was.

“Is this your way of saying you  _ want _ to go on a date with me?” Seongwu joked, nudging Minhyun’s shoulder with his own, giving him a cheeky grin.

Minhyun considered him for a second with dark eyes, lips slowly stretching into a sly smirk.  Before Seongwu could react, he leaned in close, breath coming out in hot puffs against Seongwu’s mouth.  “And if it is?”

Seongwu’s brain promptly short-circuited.  “Mr. Jennings, you’re under arrest for theft and murder, and just generally being a shitty person.”

They hauled Jennings to his feet, Minhyun smiling like a cat that got the cream while Seongwu’s face felt like it was on  _ fire _ .  They walked back to their car in silence, Jennings’ complaints and denials providing background noise.  It let Seongwu internally freak out and over analyze everything like he usually did in personal situations.

Once he’d secured Jennings in the backseat of their car, though, all he was left with was the cold late-evening air and a softly smiling Minhyun leaning against the driver side door.  

“How’d you cut ahead?” Seongwu asked.  A normal question. A safe place to start.  “We started running from the same place.”

Minhyun took a step closer.  “I took a page out of your book. Took a shortcut.”

“Through a bush?” Seongwu asked, plucking a few stray leaves from Minhyun’s hair before he realized what he was doing.

Minhyun’s eyes widened slightly, making Seongwu come to his senses and freeze.  The next second, though, Minhyun gave him a smile filled with so much affection his heart just about stopped.

“A few bushes, actually. And a hedge.”

Seongwu cleared his throat.  “Impressive. For you.”

“Uh huh.”  Another step closer.  “Is that really what you wanted to ask me, Seongwu?”

“No. Well, I was curious but,” Seongwu stopped before he could  _ really _ start rambling.  “Could I ask this in an accent? Maybe make it a little lighter-”

“Seongwu.”

“You’re no fun,”  Seongwu huffed, running a hand through his hair, not caring that he probably left it standing up at weird angles.  “You also don’t seem all that mad about losing.”

Minhyun shrugged.  “I’m not particularly happy about it.”

“But you’re not mad.”

“I have a date with the nine-nine’s best detective,” Minhyun smiled.  “How could I be mad?”

Seongwu let out a breathless, little laugh.  He scuffed the toe of his shoe against the pavement, dropping his head and looking up at Minhyun from under his lashes.  “Careful, Hwang. I might start to think you started this entire bet just to score a date with me.”

“Not entirely for that,” Minhyun snorted.  “I figured you could use a little push to work harder. Better. Did you know you haven’t submitted a single sloppy report since we started this bet? The Captain was actually impressed.”

“Did you have to try so hard to win, then?”

“Would you have believed it if I didn’t?”

“You literally went behind the Captain’s back to use Woojin,” Seongwu pointed out, amusement coloring his tone.

Minhyun cleared his throat.  “I may have lost sight of my initial objective somewhere along the way.”

Seongwu laughed.  “Oh?”

“It worked out in the end, didn’t it?” Minhyun grumbled, crossing his arms over his chest.

“Yeah, because I’m the-”

“Best detective ever?” Minhyun finished.  “So you say.”

“Nuh uh, so  _ you _ say,” Seongwu grinned, feeling bold.  “Don’t think I forgot that part of the bet.”

“You’re gonna make me regret liking you, aren’t you?” Minhyun pouted, his cheeks turning red enough that even in the low light Seongwu could see it.

“Never,” He promised.  “Embarrassed? Probably. Regret? Not a chance.”

“We’ll see about that,” Minhyun said, closing the remaining distance between them to place a soft, chaste kiss on Seongwu’s lips that sent his heart thundering.  When he pulled back, he was smiling that shy but pleased smile that was one of Seongwu’s favorites. “I want to be taken to a nice place for the date and-” he paused, looking at something over Seongwu’s shoulder, “and, Jennings is running.”

Seongwu blinked, frowning.  “What?”

Minhyun pushed at his chest, pointing.  “Jennings is running!”

Seongwu spun around and- yup, Jennings, the still-handcuffed idiot, was running.  Or trying to.

“Motherfucker.”

“If I catch him I’m putting a point in my column,” Minhyun said, and that was all the warning Seongwu got before the other man was taking off, all wide smile and shining eyes.

“What?” Seongwu shrieked, taking off after him.  “No fair! You already conceded! I won! Minhyun!  _ Minhyun! _ ”

  
  


**Author's Note:**

> Thank you for reading!


End file.
